Bill, same set of reamers Harbor Frieght has, but a bit cheaper.

Here'* the link:

http://wttool.com/p/1166-9980

pix

Here'* the UIM after returning from the machinist. Note that at .875, there was one small breakthrough into water. I stuck a paper clip into the hole to make it apparent.



top view of first photo. I think instead of reaming the manifold, the machinist decided to ream me. Note that it'* a bit off-center. About .015, I'd say.



My dirtball sleeve sits atop the upper, ready for installation. I used some #320 wet-or-dry sandpaper to rough up the hole a bit to give the JB weld some tooth for good adhesion. Wound up with a very light press fit. I tapped it into place with a brass hammer, ensuring that the bottom of the sleeve was flush with the bottom of the manifold.



All done. Note that the sleeve sticks up into the airstream quite a bit. This is for the cooling effect by the rushing intake air mentioned in previous posts.



Next up: Get some gaskets, get GREASY!

Bill,
I know for a fact after talking to the shop forman at a GM dealer that the Delphi
has been re-designed with a higher heat resistant plastic.
If I'm not mistaken Vital49 removed his original Delphi with no burn marks whatsoever. What I need to find out is if his car had the smaller tube.
If his 99 had a Delphi it was probably upgraded before he got the car.

My '99 has a Delphi (I just checked) and I've had no intake problems whatsoever, with the exception of a leaking TB gasket, which was an easy fix.

My car was assembled in late '99 (July), too. I wonder if the upgraded manifold was a production change?

I did remove my UIM at 77K with no signs of melting. The gasket looked great too. I'm not 100% sure what the manufacture date was, but it was a Delphi. As for the tube size, I'm not sure on that either.

My original UIM is now in the hands of Bob Dillion. I sent it to him last week so he could use it to retrofit an improved stove pipe. Bob, do you have those dimensions??

My lower intake gaskets? Now that'* a whole other story!!

Vital: The plastic hole in your upper miked .755 ID, with no sign of erosion of the plastic. Pictures of it with the sleeve installed are above this post.

I again thank you for sending me the manifold.

Was the tube hard to push in as was mine? I think it had a raised bump on the end similar to a rubber hose to metal pipe connection.

I honestly don't remember. It'* been a while... (almost a year). At the time I was just focused on getting it back together because we needed it for Monday AM!

I honestly don't remember. It'* been a while... (almost a year). At the time I was just focused on getting it back together because we needed it for Monday AM!

Thanks for the link on the reamers, Bob. Nice pix. Yeah the guy did ream you on that off-center deal. Hope it doesn't cause gasket problems when you go to set it in.

SSEBONNE4EVA, Is GM using Delphi now? Are Delphi and Dorman the same? Was the Delphi with the new plastic formulation available before GM reduced the diameter of the EGR pipe? The reason I am wondering all this is: if you are right about a higher heat resistant plastic, then maybe reaming and sleeving are not necessary, especially if a reduced diameter pipe is used?